In an official statement from Bryan Konietzko, he says,
"We’re thrilled for the opportunity to helm this live-action adaptation of Avatar: The Last Airbender. We can’t wait to realize Aang’s world as cinematically as we always imagined it to be, and with a culturally appropriate, non-whitewashed cast.
It’s a once-in-a-lifetime chance to build upon everyone’s great work on the original animated series and go even deeper into the characters, story, action, and world-building. Netflix is wholly dedicated to manifesting our vision for this retelling, and we’re incredibly grateful to be partnering with them.”
Production is set to begin in 2019!